Showing papers by "King Saud University published in 1988"

First‐Order Integer‐Valued Autoregressive (INAR (1)) Process: Distributional and Regression Properties

Abstract: Some properties of a first-order integer-valued autoregressive process (INAR)) are investigated. The approach begins with discussing the self-decomposability and unimodality of the 1-dimensional marginals of the process {Xn} generated according to the scheme Xn=α°Xn-i +en, where α°Xn-1 denotes a sum of Xn - 1, independent 0 - 1 random variables Y(n-1), independent of Xn-1 with Pr-(y(n - 1)= 1) = 1 - Pr (y(n-i)= 0) =α. The distribution of the innovation process (en) is obtained when the marginal distribution of the process (Xn) is geometric. Regression behavior of the INAR(1) process shows that the linear regression property in the backward direction is true only for the Poisson INAR(1) process.

Broiler performance under high stocking densities.

Abstract: 1. In two consecutive experiments a total of 4 780 broilers were reared at high stocking densities. 2. In experiment 1, the birds were housed at 10, 20, 30, 40 or 50/m2 till 6 weeks. In experiment 2 densities of 20, 40 and 50/m2 were compared; the two higher densities were reduced to 30/m2 at either 3 or 5 weeks of age. 3. In the first experiment 6‐week body weight was a curvilinear function of stocking density. Average food intake over the whole experimental period declined linearly with densities above 20/m2. 4. A slight but significant improvement in the efficiency of food utilisation was recorded from birds at high densities in the first experiment only. 5. Reducing the stocking density from 40 or 50/m2 to 30/m2 at 3 weeks increased food consumption and body weight gain and led to a recovery in their body weight by 6 weeks. 6. No significant differences were observed in mortality as a result of high stocking densities in either experiment. 7. Profit margin per m2 increased almost linearly in ...

Integer-valued moving average (INMA) process

Abstract: A simple model for a stationary sequence of dependent integer-valued random variables {Xn} is given. The sequence to be called integer-valued moving average (INMA) process, is taken as the “survivals” of i.i.d. non-negative integervalued random variables. It is argued that the model’s structure reflects to some extent the mechanism generating real life data for many counting process and consequently it is useful for modelling such processes. Various properties for the special case in which {Xn} is Poisson INMA (1) process, such as the joint distribution, regression, time reversibility, along with the conditional and partial correlations, are discussed in details. Extension of the INMA of first order to higher order moving average is considered.

Hepatitis B Infection in Saudi Arabia

Abstract: This article on the hepatitis B virus (HBV) in Saudi Arabia reviews 24 articles on HBV which have been published in national and international journals. The data of 49,312 Saudi individual...

Scanning electron microscopic study of the lingual papillae of the one humped camel, Camelus dromedarius.

Abstract: The dorsum of the camel tongue shows filiform, fungiform, circumvallate and special (wart-like) papillae. Filiform papillae are conical in shape and show different heights and thicknesses at various levels. Fungiform papillae are rounded and are surrounded by robust filiform papillae. They can also be observed on the tip of the ventral surface. They have taste pores on their surfaces. Circumvallate papillae are encircled by a primary groove and an annular pad. Their taste pores open into the grooves. A special type of filiform papillae is wart-like and has been observed on the posterior portion. These do not show taste pores.

Genito-urinary complications of brucellosis.

Abstract: Summary— Twelve cases of genito-urinary complications of brucellosis are presented. Ten patients had epididymo-orchitis, 1 presented with right hydronephrosis and 1 with haematuria and dysuria. The 10 cases of epididymo-orchitis were compared with 15 cases of acute non-specific epididymo-orchitis. The former were of longer duration and were not associated with lower urinary tract symptoms; almost all of these patients had ingested unpasteurised milk. Non-specific epididymo-orchitis had a more acute onset, shorter duration and was associated more frequently with pyuria, lower urinary tract symptoms, higher leucocyte counts and insignificant brucella titres. The distinction between these two types of epididymo-orchitis is essential, since the treatments are entirely different.

Isolation and identification of an anti-inflammatory principle from Capparis spinosa.

Abstract: The homologous polyprenols cappaprenol-12 (1), cappaprenol-13 (2) and cappaprenol-14 (3) with 12, 13 and 14 isoprene units, respectively, could be isolated by preparative HPLC from alcoholic extracts of Capparis spinosa. Testing 2 for its anti-inflammatory activity an inhibition of the carrageenan-induced paw edema in rats of 44 vs. 67% for the standard oxyphenbutazone was found.

Diabetes mellitus and Ramadan fasting: the need for a critical appraisal.

Abstract: Fasting during the holy month of Ramadan is one of the pillars of Islam and the true Moslem holds it as an article of faith. I ts time of observance varies each year because of the Muslim calendar based on lunar months. During the approximately 15 h of fasting which is from dawn to sunset, the individual must abstain from taking not only food or drinks but oral medicinal preparations as well.' However, Islam does allow the breaking of fast in Ramadan by certain categories of people such as travellers, pregnant or breastfeeding mothers, young children, menstruating women, and people with serious illness. These exemptions notwithstanding, most Moslems sti l l choose to fast, including those with a chronic metabolic disease like diabetes mellitus. Within the last decade or so, diabetes mellitus has emerged as a major health problem among the Moslem populations of the rapidly developing Gulf countries. Consequently, health practitioners who are treating Moslem diabetic patients must be able to counsel them on how to fulfil their religious and spiritual obligations without danger to their health. A search of the Englishspeaking literature has turned up only a few anecdotal accounts in the form of letters to the editor'-3 and abstracts from symposia on diabetes held in Saudi Arabia'5 on the subject of diabetes mellitus and Ramadan fasting. The disparate views expressed in these brief reports and the paucity of information emphasizes the need to give the subject greater attention. It is now generally accepted that optimum control of blood glucose concentrations is a desirable goal in diabetes' and it involves a proper mix of a satisfactory diet with or without exercise, oral hypoglycaemic agents (OHAS) or insulin. In this article, we review briefly the metabolic changes during fasting in healthy individuals, assess the potential risks of fasting to a diabetic patient, and finally offer a few suggestions for the counselling of

Walking characteristics in central riyadh, saudi arabia

Abstract: In recent decades, the importance of walking as a significant urban travel model in the total transportation system of an area has been recognized in the industrial nations of the West. In rapidly ...

Ligaments associated with lumbar intervertebral foramina. 1. L1 to L4.

Abstract: Lumbar intervertebral foramina have been studied by dissection of fetal and adult cadaveric spines. The results show that these foramina are crossed by ligaments which subdivide the opening into smaller compartments for the structures traversing it. At L1-L4, there appears to be a basic pattern of arrangement of the ligaments. The bands are tougher in the upper lumbar region and become steadily thinner caudally. Evidence from the study suggests that these ligaments are probably normal components of the intervertebral foramen. The significance of these findings is discussed.

Cytological Effects of Khat (Catha Edulis) in Somatic and Male Germ Cells of Mice

Abstract: Cytological effects of khat (Catha edulis), a popular drug of abuse from Southern Arabia and Eastern Africa, have been studied in Swiss albino mice. The studies on the somatic system involved the use of micronucleus test and the cytological analysis of the mitotic index in the femoral cells of mice. In the micronucleus test, the mice were treated with different doses of khat extract (125, 250 and 500 mg/kg, p.o.) 30 and 6 hours before sacrificing the animals. The polychromatic erythrocytes were screened for the induction of micronuclei. For the analysis of bone marrow cytotoxicity, the mice were treated with the dose of 125, 250 and 500 mg/kg, body weight, p.o. daily for 5 consecutive days. The animals were sacrificed and the femoral cells were microscopically examined for the mitoses. Following the same schedule of treatment, studies on the cytogenetic analysis of meiotic chromosomal aberrations and the sperm head abnormality were undertaken. Khat extract significantly increased the frequency of ...

A revision of the upper part of the Saq Formation and Hanadir Shale (lower Ordovician) of Saudi Arabia

Abstract: The previously termed Hanadir Shale of Saudi Arabia is described and re-defined as the Hanadir Formation. At the type locality of Al Hanadir the unit is probably entirely of Llanvirn age while further north shelly faunas of possible Llandeilo age occur in the upper part. Trace fossil assemblages with abundant cruzianids (C. furcifera, C. rugosa, C. goldfussi), Pelecypodichnus, Didymaulichnus and Diplichnites indicate an Arenig age for beds in the upper part of the underlying Saq Formation, while the top of this unit yielded hitherto unrecorded pendent and biserial scandent graptolites, a sparse shelly fauna of lingulacean brachiopods, Neseuretus sp. and the trace fossils Cruziana? imbricata and Phycodes.

Reduction in codimension of mixed foliate CR-submanifolds of a Kaehler manifold

Abstract: Starting with a proper mixed foliate Ci?-submanifold M of dimension 2p-\-q in a hyperbolic complex space form M(—4) of dimension m(rn^2p+2q), it has been proved that under a suitable condition on second fundamental form there exists a (2p+2q) -dimensional totally geodesic submanifold M' of M such that Mis a mixed foliate Ctf-submanifold of M'.

Ligaments associated with lumbar intervertebral foramina. 2. The fifth lumbar level.

Abstract: The lumbosacral spines of two fetal and twelve adult cadavers have been studied by dissection. Evidence shows that the fifth lumbar intervertebral foramen is crossed on its external aspect by a strong, cord-like corporotransverse ligament passing obliquely downwards, forwards and medially from the inferior aspect of the accessory process of the fifth lumbar vertebra to the lateral surface of the intervertebral disc and the adjacent parts of the bodies of the fifth and first sacral vertebrae. Superficially, the ligament is related to another flat band--the lumbosacral hood. Together these ligaments separate and provide openings for the sympathetic ramus, the ventral ramus and blood vessels related to the intervertebral foramen. On the dorsal aspect, a tripartite ligament, the mamillo-transverso-accessory ligament, bears important relationships to the subdivisions of the dorsal ramus and also the zygapophyseal joint. The significance of these findings is discussed.

Evaluation of some Pharmacological, Microbiological and Physical Properties of Zizyphus spina-christi

Abstract: Zizyphus spina-christi is a commonly available plant used by Saudi folk medicine practitioners for various purposes. The experimental testing of these claimed properties in animals, using the ethanolic extract of the leaves, showed that it has a considerable anti-inflammatory and moderate antipyretic activities. It also inhibited the growth of Bacillus subtilis. However, no analgesic or diuretic activity could be demonstrated. The aqueous extract of the leaves exhibited surface activity with critical micelle concentration found at 0.25% w/v concentration.

Goblet cell population among patients with inactive trachoma.

Abstract: Trachoma is a chlamydial disease that affects millions of people each year, particularly in developing countries. In the chronic phase, inflammation causes scarring of the conjunctiva followed by dry eye which can result in blindness. Trachoma may cause dryness of the eye by decreasing mucus production and aqueous secretions. Conjunctival impression cytology was carried out to determine the goblet cell population among patients with trachoma.

Patterns of breastfeeding and weaning in Saudi Arabia.

Abstract: The patterns of breastfeeding and weaning were studied in 4 groups of Saudi children: Privileged urban children; children representing the average urban population; less privileged urban children, and rural children from 3 different areas. The data represented retrospective and actual information and were analyzed according to the life table technique. The median duration of breastfeeding of rural, urban low, urban average and urban privileged children was 17.8 months, 10.8 months, 7.5 months and 2.1 months, respectively. In all groups the rate of breastfeeding was lower in young compared with old mothers. Thus the median duration of breastfeeding was 11.7 months for rural mothers less than 23 years and 23.6 months for mothers greater than 31 years. Corresponding figures for urban low mothers were 3.4 months and 11.4 months, respectively. By one month 52 percent of privileged and 42 percent of urban low children were started on bottle. By contrast, 26 percent of rural children were started on bottle at 6 months. At 6 months, 6 percent of rural children were started on any kind of solid foods compared with 90 percent of privileged children; at 12 months the figures were 33 and 96 percent, respectively. The data indicated a successive decline in the duration of breastfeeding with increasing affluence, and late introduction of weaning foods to rural children.